Hi Dave, I have the same problem. I bought the car (Golf 2004)last Thursday and radio turns on by itself. Some notices:
- radio time to time tries to play CD eventhough there is no CD for ~2 seconds and then it switched back to radio.
- a couple of time there has been also CD error message.
I'm interested to hear your car's serial number, my serial number is WVWZZZ1KZ5W111700, perhaps they have exactly the same hw and sw. When your Golf started to have this 'intelligency'?
JV, March 2008